Even if you don't know whether you have crab grass or not, you would probably be able to identify it once it was described to you. That's because crab grass is one of the most common grass weeds found in a lawn. Crab grass forms dense mats of grass that spread out along the ground in low-growing blades. This type of crab grass is often observed growing through cracks in the sidewalk with tiny, hair-like roots. Remove crab grass through a system of lawn improvement.
Water your lawn to loosen the soil. This will make crab grass easier to remove.
Dig up crabgrass with a hoe or garden trowel, being sure to discard all of the roots. Discard the plant.
Set your lawn mower to a higher setting when cutting grass. This will shade the ground and prevent crab grass seed from getting enough sunlight to become re-established.
Seed a heartier grass onto your lawn, such as Zoysia grass. To do this, rake the lawn with a rake, and then spread grass seed with a broadcast spreader. Thicker, heartier grasses will prevent crab grass from returning.
Apply a pre-emergent crab grass spray to your lawn in the spring to prevent crab grass from returning.